-
[
Methods Mol Biol,
2006]
The nematode Caenorhabditis elegans provides numerous experimental advantages for the identification and characterization of genes required for the function of the nervous system. These advantages include forward and reverse genetic tractability, a relatively simple body plan with an invariant cellular lineage, and a fully sequenced and well-annotated genome. However, one limitation of C. elegans is the relative scarcity of electrophysiological data from excitable cells. To address this limitation, high-resolution cellular techniques for probing the roles of specific gene products in the C. elegans nervous system have been recently developed. This chapter will provide an overview of the technical requirements for patch-clamp electrophysiological analysis of C. elegans neurons and muscle cells, as well as provide some illustrative examples of insights gained from the pairing of electrophysiological techniques with molecular and genetic analysis.
-
[
Trends Neurosci,
2003]
The nematode Caenorhabditis elegans has long been popular with researchers interested in fundamental issues of neural development, sensory processing and behavior. Recently, advances in applying electrophysiological techniques to C. elegans have made this genetically tractable organism considerably more attractive to neurobiologists studying the molecular mechanisms of synaptic organization and function. The development of techniques that involve voltage-clamp of specific neurons and muscles has allowed the coupling of genetic perturbation techniques with electrophysiological analyses of nervous system function. Recent studies combining these biophysical and genetic techniques have provided novel insights into the mechanisms of presynaptic neurotransmitter release, postsynaptic responses to neurotransmitters and information processing by neural circuits.
-
[
Curr Top Dev Biol,
2000]
The main advantage of C. elegans as an experimental model lies in its simplicity. The full-grown adult is about 1 mm in length and composed of fewer than 1000 somatic nuclei. It has a short reproductive cycle of approximately 3 days and simple nutritional requirements, feeding primarily on bacteria....
-
[
Methods Mol Biol,
2006]
High-pressure freezing (HPF) is capable of converting liquid water, to a depth of approx 0.6 mm, into amorphous ice nearly instantaneously. At midbody, an adult Caenorhabditis elegans hermaphrodite approaches its widest girth of approx 0.1 mm. In theory, an entire living adult animal can be physically immobilized instantly in amorphous ice by HPF, thus, providing a unique opportunity to examine cellular architecture with exquisite spatial preservation. The following chapter will discuss, in detail, procedures for freezing C. elegans under high pressure, for embedding frozen samples in resin after a freeze-substitution step, and for the postembedding immunogold labeling of proteins contained within thin sections of embedded animals. These protocols enable high-resolution analysis of both morphological features and molecular domains within most tissues of C. elegans.
-
[
2017]
Caenorhabditis elegans is a 1-mm-long free-living nematode that feeds on bacteria. The feeding organ of C. elegans is a pharynx, a neuromuscular tube responsible for sucking bacteria into the worm from outside, concentrating them, and grinding them up (Doncaster 1962, Seymour et al. 1983). The basic mechanics and the neurons and muscles used to execute feeding motion are important for understanding several feeding behaviors and are therefore briefly described. More details regarding cellular and nuclear composition, the structure, electrophysiology, and the molecular components can be found in Avery and You (2012).
-
[
Studies of History & Philosophy of Science,
1998]
In 1963, just a year after the researchers of the Medical Research Council (MRC) Unit of Molecular Biology in Cambridge, joined by some other research groups, has moved from various scattered and makeshift buildings in the courtyard of the Physics Department to a lavishly funded four-storey laboratory, B. Lush, the Principal Medical Officer of the MRC, came to inquire about their plans for future expansion. He indicated that the MRC wished to build the laboratory up to what the principal researchers considered its 'final size' until their retirement, which meant planning ahead for at least 15 years. This surprising move was doubtless prompted by the recent award of the Nobel Prize to three members of the laboratory, Max Perutz, John Kendrew and Francis Crick, for their work on the molecular structure of proteins and nucleic acids. The triple award had propelled the new Laboratory of Molecular Biology into the limelight, and the MRC was interested in securing optimal research conditions for this prestigious group of researchers.
-
[
Annu Rev Neurosci,
1993]
Behavior arises through the interplay of innate properties of the nervous system, environmental stimuli, and experience. An opportunity to integrate neuronal and genetic approaches to study behavior is provided by the soil nematode Caenorhabditis elegans. C. elegans is attractive for study because of the simplicity and accessibility of its nervous system. The adult hermaphrodite is 1 mm long, and its nervous system is composed of only 302 neurons. The nucleus of each neuron can be identified in live animals by differential interference microscopy, and the cell lineage that gives rise to each of these neurons has been described in its entirety. C. elegans develops to adulthood in about three days at 25C, which facilitates observation of its
-
[
J Fungi (Basel),
2018]
<i>C. elegans</i> has several advantages as an experimental host for the study of infectious diseases. Worms are easily maintained and propagated on bacterial lawns. The worms can be frozen for long term storage and still maintain viability years later. Their short generation time and large brood size of thousands of worms grown on a single petri dish, makes it relatively easy to maintain at a low cost. The typical wild type adult worm grows to approximately 1.5 mm in length and are transparent, allowing for the identification of several internal organs using an affordable dissecting microscope. A large collection of loss of function mutant strains are readily available from the <i>C. elegans</i> genetic stock center, making targeted genetic studies in the nematode possible. Here we describe ways in which this facile model host has been used to study <i>Candida albicans</i>, an opportunistic fungal pathogen that poses a serious public health threat.
-
[
Angew Chem Int Ed Engl,
2011]
This Review discusses the potential usefulness of the worm Caenorhabditis elegans as a model organism for chemists interested in studying living systems. C. elegans, a 1 mm long roundworm, is a popular model organism in almost all areas of modern biology. The worm has several features that make it attractive for biology: it is small (<1000 cells), transparent, and genetically tractable. Despite its simplicity, the worm exhibits complex phenotypes associated with multicellularity: the worm has differentiated cells and organs, it ages and has a well-defined lifespan, and it is capable of learning and remembering. This Review argues that the balance between simplicity and complexity in the worm will make it a useful tool in determining the relationship between molecular-scale phenomena and organism-level phenomena, such as aging, behavior, cognition, and disease. Following an introduction to worm biology, the Review provides examples of current research with C. elegans that is chemically relevant. It also describes tools-biological, chemical, and physical-that are available to researchers studying the worm.
-
[
Ing Rech Biomed,
2008]
Because the entire genome of Caenorhabditis elegans (C. elegans) is available for exploration since 1998, several information have been retrieved about the global interest of this organism when it became apparent that the similarity of genes in this 1 mm length nematode and those in humans is remarkable, with approximately 67% of genes that are associated with human disease having homologues in the worm genome. C. elegans worms can be easily maintained on various food-sources and culture media allowing testing for molecules or treatments in combination with different genetic mutants backgrounds as well as RNA interference (RNAi). Because of regulatory pathways conservation between humans and worms, several interesting strategies can be developed to facilitate drugs screenings on specific targets as well as to decipher complex physiological programmed traits with potential identification of new therapeutic targets interesting for human health. By using specific examples, we propose to introduce how to use the already available C. elegans data-cross that can be used as a basis for developing new therapeutic targets identification strategies.